package myHomework;

import java.util.Scanner;

public class Work4 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int score = scanner.nextInt();
        if(score<60)
        {
            System.out.println("不及格");
        }else if(score<70){
            System.out.println("及格");
        }else if(score<80){
            System.out.println("中");
        } else if (score<90) {
            System.out.println("良");
        }else{
            System.out.println("优");
        }
    }
}
